This is a randomized controlled trial to evaluate the effects of a new dental tool handle design on hand and arm symptoms and function among 120 dental hygienists and dentists who perform dental scaling. Dentists and dental hygienists are at increased risk for the development of upper extremity musculoskeletal disorders such as carpal tunnel syndrome and tendonitis. These disorders are responsible for more disability retirement in these professions than any other cause. The primary risk factors associated with these disorders are the high pinch force and awkward wrist postures associated with periodontal work, such as dental scaling. Preliminary data from a laboratory study suggests that modifying the diameter and weight of the dental tool can have a significant impact on the pinch force and forearm muscle load during a simulated scaling task. This is a 3 month intervention study in the practitioner's workplace. Participants will be randomized to receive a new tool design (large diameter and lightweight) or a conventional tool design. They will use the tool for all of their periodontal work for a 3 month duration. At the end of every week they will be asked to rate their hand and arm pain, fatigue and paresthesias, hand function, pain medication usage, and the number of hours of scaling for that week. Change in hand symptom intensity over the 3 month period will be compared between groups while adjusting for potential covariates (e.g., age, gender, occupation, scaling hours per week, work hours, non-work hand activity, etc.). At the end of the intervention, a randomly selected subset of 20 subjects from each group will perform a standardized scaling task on a mannequin to measure pinch force. The study may identify a tool handle design that prevents (primary or secondary) musculoskeletal pain and disability among dentists and dental hygienists. NARRATIVE Dentists and dental hygienists experience elevated rates of musculoskeletal disorders, such as carpal tunnel syndrome and tendonitis, primarily due to the high pinch force required for dental scaling. There is evidence that a lighter and larger diameter tool can significantly reduce the pinch force. This randomized controlled study will deterimine if dentists or dental hygienists who use such a tool report less hand and arm pain compared to those who continue to use the conventional tool design. [unreadable] [unreadable] [unreadable]